Elastic bed plate



(No Model.)

P. KNOCH. ELASTIC BBD PLATE.

110.571,618. Patented Nov. 17, 1896.

{I1/VENTURI WTNESSES.

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UNITED STATES PATENT rricno PAUL KNOCII, OF ADLER-SHOE, GERMANY, ASSIGNOR TO HEINRICH PI'IILLIPP KNOCI-I, OF SAME PLACE.

ELASTIC BED-PLATE.

SPECIFICATION forming part of Letters Patent No. 571,618, dated November 17, 1896.

` Application filed September 6, 1895. Serial No. 562,018. {No model.)

To (LZ/' whom t may concern: being confined to that part of it which is Beit known that I, PAUL KNOCH, of Adlersactually in contact with the rail. This par- 5o hof, near Berlin, Germany, have invented a ticularity further reduces the danger of innew and Improved Elastic Bed-Plate, of which jury to the plate. 5 the following is a full, clear, and exact de- The new elastic supporting-plate may be scription. safely used without an interposed iron plate,

My invention relates to elastic supportingas such an additional hard plate is not neces- 5 5 plates for railway-rails, and has for its obj ect sary to protect the upper surface of the felt, to increase the strength an d durability of such which is sufficiently hardened by impregnatio plates. ing it with suitable substances or solutions.

Hitherto there have been employed felt lVhile manycoinpoundsinaybe used to prosupporting-plates, impregnated uniformly duce the superficial hardening above referred 6o throughout, and their upper surface on which to, I have found that a Very efficient protecthe rail rests therefore is just as yielding as tion is afforded to the supporting-plate bythe i 5 the remainder of the supporting-plate. Since following described process: The felt having in order to be elastic the felt su pporting-plate first been treated in its entire body to increase niust be soft, the rail is not securely supported its durability throughout, it is coated with a 65 unless an additional iron plate is interposed, layer of glue, which is allowed to penetrate to and Avery often Jche edges of the rails base will a depth of about four millimeters, and this zo cutinto the felt supporting-plate, thereby renlayer is then impregnated with chrome-alum, dering it useless and necessitating the subbichroinate of potash, soda, formalin, or the stitution of a new one. My present invention like, and allowed to dry. Another method 7o obviates this defect; and it consists in a supconsists in employing a solution of india-rubporting-plate made of felt or similar yielding ber for impregnating the plate, and then vul- 2 5 material, but prepared inaparticularmanner canizing the rubber; or the upper layer of at its upper surface, so that an upper layer of the plate maybe impregnated with a resi nous suitable thickness will be hard enough to supsolution. 7 5 port the rail without any danger of the plate It will be understood that when there is any being out by the rails edges. danger of the under side of the plate being 5o Reference ishad to the accompanyingdraw injured by great pressure the impregnation ings, forming a part of this specification7 in is effected on both sides, the central portionj which similar characters of reference indicate however, remaining soft, so that the plate is 8o corresponding parts in all of the views. still yielding enough to serve as an elastic Figure l is a plan View of a bed-plate consupporting-plate. This is shown in Fig. 2, 'f5 structed after the manner of iny invention. as before described.

Fig. 2 is an edge View, and Fig. i2 is an edge Having thus described my invention, I View of a inodiication. claim as new and desire to secure by Letters 85 The felt is provided with a hardened surface Patent or portion a and with an elastic portion b, the 1. A supporting-plate consisting of a yield- 4o hardened surface being on one side, and in ing absorbent material having a surface inipractice this side is arranged upward. pregnated with a hardening substance, the

Fig. 2 shows each side of the felt provided hardened substance extending partly into the 9o with a hardened surface a and with the elasplate and leaving the remainder of the plate tic portion?) sandwiched between the two. in its original yielding forni, substantially as XVith reference to this invention it will be described. seen that the weight of the rail and of cars 2. A supportingplate forined of yielding passing thereover is evenly distributed on the niaterialhaying one surface impregnated with 95 whole surface of the feltA support, instead of a hardened substance, the hardening substance extending partly into the plate and leaving' the remainder of the plate in its original yielding' form, substantially as described.

A method of forming supporting-plates, the method consisting in first impregnating a yielding plate with a solution of india-rubber, the solution being permitted to extend partly into the plate and second in Vuleanizing the solution of india-rubber so as to form a hardened surface for the plate and so as to leave zo the remainder of the plate in its original yielding form, substantially as described.

In Witness whereof I have hereunto set my hand in presence of two Witnesses.

PAUL KNOCH. Witnesses OTTO HABERMEHL, WILHELM SGHWISTHAL. 

